[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Xen-devel] [PATCH 01/44] kernel: Add support for poweroff handler call chain
- To: Guenter Roeck <linux@xxxxxxxxxxxx>, linux-kernel@xxxxxxxxxxxxxxx
- From: Philippe Rétornaz <philippe.retornaz@xxxxxxxxx>
- Date: Tue, 07 Oct 2014 09:46:59 +0200
- Cc: linux-m32r-ja@xxxxxxxxxxxxxxxxx, linux-mips@xxxxxxxxxxxxxx, linux-efi@xxxxxxxxxxxxxxx, linux-ia64@xxxxxxxxxxxxxxx, Heiko Stuebner <heiko@xxxxxxxxx>, linux-sh@xxxxxxxxxxxxxxx, devicetree@xxxxxxxxxxxxxxx, Pavel Machek <pavel@xxxxxx>, devel@xxxxxxxxxxxxxxxxxxxx, linux-s390@xxxxxxxxxxxxxxx, lguest@xxxxxxxxxxxxxxxx, linux-c6x-dev@xxxxxxxxxxxxx, linux-hexagon@xxxxxxxxxxxxxxx, Alexander Graf <agraf@xxxxxxx>, linux-acpi@xxxxxxxxxxxxxxx, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxxx, Len Brown <len.brown@xxxxxxxxx>, user-mode-linux-devel@xxxxxxxxxxxxxxxxxxxxx, linux-pm@xxxxxxxxxxxxxxx, linux-xtensa@xxxxxxxxxxxxxxxx, adi-buildroot-devel@xxxxxxxxxxxxxxxxxxxxx, linux-m68k@xxxxxxxxxxxxxxxxxxxx, linux-am33-list@xxxxxxxxxx, linux-tegra@xxxxxxxxxxxxxxx, openipmi-developer@xxxxxxxxxxxxxxxxxxxxx, linux-metag@xxxxxxxxxxxxxxx, linux-arm-kernel@xxxxxxxxxxxxxxxxxxx, linux-cris-kernel@xxxxxxxx, linux-parisc@xxxxxxxxxxxxxxx, "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>, linux-alpha@xxxxxxxxxxxxxxx, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>, Romain Perier <romain.perier@xxxxxxxxx>, linuxppc-dev@xxxxxxxxxxxxxxxx
- Delivery-date: Tue, 07 Oct 2014 07:53:56 +0000
- List-id: Xen developer discussion <xen-devel.lists.xen.org>
Hello
This seems exactly what I would need on the mc13783 to handle cleanly
the poweroff,
but after reading this patchset I have the following question:
[...]
+/*
+ * Notifier list for kernel code which wants to be called
+ * to power off the system.
+ */
+static ATOMIC_NOTIFIER_HEAD(poweroff_handler_list);
[...]
+void do_kernel_poweroff(void)
+{
+ atomic_notifier_call_chain(&poweroff_handler_list, 0, NULL);
+}
+
It seems that the poweroff callback needs to be atomic as per
_atomic_notifier_call_chain documentation:
"Calls each function in a notifier chain in turn. The functions
run in an atomic context"
But this is a problem for many MFD (mc13783, twl4030 etc ...) which are
accessible on only a blocking bus (SPI, I2C).
What I am missing here ?
Thanks,
Philippe
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel
|
